Ultrasonic Characterization of Advanced Composite Materials

With increased use of composite materials in critical structural applications it is more important than ever to independently assure structural integrity. Complexity of the advanced composite materials including layered and bonded structures represents challenges in developing optimized ultrasonic tests. Traditional ultrasonic NDT methods are inappropriate and often misleading when applied to anisotropic and nonhomogeneous composite materials. In advanced technology applications such as aerospace and with industrial emphasis on economics and safety, it is critical to develop robust and practical NDT mehtods. Recent analytical and experimental work with ultrasonic guided wave methods using laser generation and minature ultrasonic receivers enables novel automated and rapid testing of these advanced composite structures.By optimizing and customizing ultrasonic trunsduction proces, measurments of material properties and defect conditions can can be estimated along in-plane sound propagation path. From acoustic response, one can develop meaningful estimate of material modulus, fatigue damge, thermal damge and sense mechnical defect conditions without need to pointvise scan the complete structure.